# Python pow Example, Power Operator

This Python example uses the pow built-in along with the power operator that has 2 stars. Pow can be used with 3 arguments to do modulo division.**Pow.** In exponentiation, one number is multiplied by itself. This is performed with the pow method, a built-in. With two stars, we can also take exponents.

Numbers**In Python,** two stars and pow are equivalent. So we can use whichever one seems clearest. I feel pow is clearer, but I rarely need exponents in programs.

**First example.** Here we use pow and the exponent operator. We see that 2 squared is 4 (because 2 times 2 is four). You should know this from math class.

**Here:** We use both the two-star operator and the pow method. We see the results of both syntax forms are equal.

**Python program that uses pow, exponents**
*# Two squared is four.
# ... These syntax forms are identical.
*print(2 ** 2)
print(__pow__(2, 2))*
# Two cubed is eight.
*print(2 ** 3)
print(__pow__(2, 3))
**Output**
4
4
8
8

**3 arguments.** Pow can be used with 3 arguments. The third argument is for modulo division. The result of the exponentiation operation is divided by that number. The remainder is returned.

**Here:** We take the square of 3 to get 9. And then we divide nine by five, so we have a remainder of 4.

**Note:** This version of pow may improve performance. But I have never needed this in a real Python program.

**Python program that uses pow with 3 arguments**
*# Compute 3 squared.
# ... This is 9.
# ... Perform 9 modulo 5 to get result of 4.
*result = __pow__(3, 2, 5)
print(result)
**Output**
4

**Python documentation.** The Python documentation is pretty good. Let's see what it says about pow. It states that pow and the two-star operator are equivalent.

**Quote:** The two-argument form pow(x, y) is equivalent to using the power operator.

Built-in Functions: python.org

**A main goal** of Python is syntax clarity. Python programs are easy to read and to write. With pow, we have a choice of syntax to use.

**For developers** who use many exponentiation operations, two stars might be clearer. But pow is often a less-common operation. For this reason it is probably a better choice overall.

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